Blizzard made the same...mistake is not quite the word I want...with the story of Vessel of Hatred as Square Enix did with Dawntrail. They both assume or take it for granted that the player likes the main NPC, Neyrelle in VoH and Wuk Lamat in Dawntrail, to much greater degree than is warranted. If the player doesn't like the NPC, then the story is actively annoying. At the end of the main campaign in base D4, Neyrelle does something quite stupid, and a lot of player base is out of charity with her because of that. So VoH insisting that the player is deeply concerned with Neyrelle rubs you the wrong way.
Also, in general, I think RPGs should refrain from forcing emotions on the player character. Gamers are notoriously contrary, and insisting that "No, your character feels X" is a surefire way to get their hackles up.
Otherwise, though, the story is quite good. It delves into Nahantu and Akarat, and I really liked the fleshing out of the Akarat mythology.
Gameplay-wise, I kind of wish the new Season hadn't started right away. I wanted to do the new campaign on my original Rogue which did the main campaign. But that character is an eternal character, and I wouldn't have made any seasonal progress. In the end, I basically made a carbon-copy of my Rogue and did the story in Seasonal. D3's rebirth feature would have been a nice compromise.
Apparently the new class, Spiritborn, is completely broken. One of the community sites rates builds in tiers, using S-A-B-C. They introduced a new "S+" tier, just for Spiritborn.
I'm playing a Flurry Rogue, and it's going pretty well. Blizzard has spread out the rewards nicely. Bouncing around and doing a bit of different content every play session works very nicely.
The way the new difficult tiers have settled with Torment levels is very nice as well. It's good that almost all content scales together. The only exception is the Pit, which is all about pushing higher difficulties.
All in all, Vessel of Hatred is a good expansion. The story is pretty good, and the rest of the game is in a good position. The only glaring issue is the power level of Spiritborn, and hopefully Blizzard will bring them back in line for the next season.
